Field of the Invention
The present invention relates to a technique for presenting Mixed Reality (MR).
Description of the Related Art
Recently, studies of MR aiming at seamless combination of a physical space and virtual space have been made actively. An image display device which presents mixed reality is, for example, a device which displays an image obtained by superimposing and rendering, on an image of a physical space that is sensed by an image sensing device such as a video camera, an image in a virtual space (for example, a virtual object or character information rendered by computer graphics) that is generated in accordance with the position and orientation of the image sensing device. As such a device, for example, a Head Mounted Display (HMD) is usable, e.g., see Japanese Patent Application No. 2006-320872, Japanese Patent Application No. 2010-189458, and Japanese Patent Laid-Open No. 2007-172596. The image display device is also implemented by an optical see-through method of displaying, on an optical see-through display mounted on the head of a user, an image in a virtual space that is generated in accordance with the position and orientation of the viewpoint of the user. There is disclosed a method using markers for calculating the position and orientation of an image sensing device from an image in a physical space that is acquired from the image sensing device (e.g., see Japanese Patent Application No. 2006-320872, and Japanese Patent Laid-Open No. 2007-172596).
When building a system which obtains the position and orientation of the viewpoint by using an image in the physical space including markers and enables a user to experience MR by using the obtained position and orientation of the viewpoint, a user having little knowledge of MR does not know an arrangement pattern of markers that stabilizes calculation of the position and orientation of the viewpoint.